The turnover of messenger RNA (mRNA) in two intrahepatically transplantable hepatoma (5123 and 19) and host livers of Buffalo rats was evaluated with four different approaches. [14C]Orotic acid incorporation into the rapidly labeled peak between 18S and 4S of total polyribosomal RNA was measured. In vitro RNase assay of [14C]orotic acid-labeled mRNA of polyribosomes was utilized. The decay of m...

References 1. Webster DR, Becroft DMO, Suttle DP. Hereditary orotic aciduria and other disorders of pyrimidine metabolism. In: Scriver CR, Beaudet AL, Sly WS, Valle D, eds. The metabolic bases of inherited disease, 7th ed. New York: McGraw-Hill, 1995:1799–837. 2. Potter M, Hammond JW, Sim KG, Green AK, Wilcken B. Ornithine carbamoyltransferase deficiency: improved sensitivity of testing for pro...

The epithelium of rat small intestine was radioautographed to examine whether RNA is synthesized by the salvage pathway as shown after [3H]uridine injection or by the de novo pathway as shown after [3H]orotic acid injection. The two modes of RNA synthesis were thus investigated during the migration of columnar cells from crypt base to villus top, and the rate of synthesis was assessed by counti...

Considerable knowledge concerning purine metabolism has been obtained from chemical and isotopic studies of urinary uric acid. Corresponding information in man is lacking for the closely related field of pyrimidine metabolism. The availability of ring-labeled orotic acid as a specific pyrimidine precursor (1), together with the presence of pseudouridine (5-ribosyluracil) and uracil, as specific...

Lovatt et al. (1979 Plant Physiol 64: 562-569) have previously demonstrated that end-product inhibition functions as a mechanism regulating the activity of the orotic acid pathway in intact cells of roots excised from 2-day-old squash plants (Cucurbita pepo L. cv Early Prolific Straightneck). Uridine (0.5 millimolar final concentration) or one of its metabolites inhibited the incorporation of N...

1. Canine pancreas slices were incubated with [6-(14)C]orotic acid and the rate of its incorporation into RNA was measured. RNA was fractionated by shaking homogenates with phenol at 2 degrees , 50 degrees , 65 degrees and 80 degrees . Cytoplasmic RNA was extracted at the lowest temperature and nuclear RNA at the higher temperatures. The samples were centrifuged through sucrose gradients and th...

Method VFD0134J_E HPLC Column: Eurokat H, 10 μm, 300 x 8 mm Order No. 30GX340EKN Phase: Eurokat H, 10 μm Eluent: 0.01 N Sulfuric acid Gradient: Isocratic Flow rate: 0.6 ml/min Temperature: 60 °C Volume: 20 μL (Standard) Detection: UV, 210 nm Substances: Orotic acid, Lactic acid and Acetic acid